Insulated article and method of making same

Abstract

A tube is thermally insulated for protecting a fluid flowing therethrough from a high includes temperature surrounding environment of a gas turbine engine. The tube includes a conduit, an insulating layer wrapped around the conduit, and an elongated contractible braided sleeve for preventing a separation of the insulating layer from the rigid conduit. The contractible braided sleeve is flexible along a longitudinal axis thereof and removably pulled over the insulating layer to snugly surround and maintain the insulating layer around the conduit.

1. A thermally insulated tube for conducting a fluid in a high temperature environment of a gas turbine engine, the tube comprising:
 a conduit defining a flow path for conveying the fluid through the high temperature environment of the gas turbine engine, the conduit having an outer surface; 
 a thermal insulation layer disposed around the conduit and having an inner surface in contact with the outer surface of the conduit, the thermal insulation layer comprising an insulating tape having an adhesive back provided on said inner surface and adhering directly to the outer surface of the conduit, the adhesive back being bonded to the outer surface of the conduit, thereby preventing separation of the thermal insulation layer from the conduit; and 
 a removable protective layer surrounding and securely compressing the thermal insulation layer around the conduit, the protective layer comprising an expendable braided sleeve reversibly shrunk around the insulating tape, the braided sleeve being removable to provide access to the insulating tape on the conduit. 
 
     
     
       2. The insulated tube defined in  claim 1 , wherein the expendable braided sleeve is configurable between and expended state in which an inner diameter of the braided sleeve is greater than an outside diameter defined by the insulating tape on the conduit, and a contracted state in which the braided sleeve provides assistance in holding the thermal insulation layer on the conduit. 
     
     
       3. The insulated tube as defined in  claim 1 , wherein the conduit is rigid. 
     
     
       4. The insulated tube as, defined in  claim 3 , wherein the thermal insulation layer consists of an insulating adhesive backed tape wrapped around the rigid conduit. 
     
     
       5. The insulated tube as defined in  claim 4 , wherein the tape is one of glass fiber insulation tape, tape including ceramic material and silica-based fiber tape. 
     
     
       6. The insulated tube as defined in  claim 1 , wherein the braided sleeve comprises a material selected from the group consisting of: high temperature glass fibers, stainless steel, nickel-plated copper, silver-plated copper, and heat-treated aluminium coated fibreglass. 
     
     
       7. The insulated tube as defined in  claim 1 , further comprising at least two spaced-apart clamps compressing the removable protective layer around and against the conduit. 
     
     
       8. A thermally insulated tube for protecting a fluid flowing through the tube from a high temperature surrounding environment of a gas turbine engine, the insulated tube comprising:
 a rigid conduit defining at least one bend; 
 an insulating layer wrapped around the rigid conduit along at least a longitudinal portion thereof including the bend, the insulating layer having an adhesive provided on an inner face thereof and adhering to an outer surface of the rigid conduit; and 
 an elongated contractible braided sleeve preventing a separation of the insulating layer from the rigid conduit, the contractible braided sleeve being flexible along a longitudinal axis thereof and removably pulled over the insulating layer to snugly surround and maintain the insulating layer around the longitudinal portion of the rigid conduit. 
 
     
     
       9. The insulated tube as defined in  claim 8 , wherein the elongated contractible braided sleeve compresses the insulating layer around all the longitudinal portion of the conduit. 
     
     
       10. The insulated tube as defined in  claim 8 , wherein the contractible braided sleeve includes a braided material made of at least one of high temperature glass fibers, stainless steel, nickel-plated copper, silver-plated copper, and heat-treated aluminium coated fibreglass. 
     
     
       11. The insulated tube as defined in  claim 8 , wherein the insulating layer includes a layer of insulating tape. 
     
     
       12. The insulated tube as defined in  claim 8 , wherein the insulating layer includes a layer containing at least one of glass fiber, ceramic material and silica-based fiber.